Can't access TIBX file with Windows Explorer

I recently had to get my laptop rebuilt. After I got it back and re-installed TI2020 (Build 25700) I was able to access my USB drive with my previous backups on it and drag and drop my files to recover everything. I did run into a problem when trying to run my first backup though (using the Survival Kit option). I evidently had an error on my C: drive and every attempt to run failed with an error message (failed to start child process). I opened a ticket and eventually got the drive error resolved.  Once that was corrected, my survival kit backup to USB worked fine. Just this morning I had the need to get into the backup to check for a change I made. Double-Clicking the backup file no longer opened an explorer window to see the files (although it worked fine just a couple of days ago after the re-install). I was curious and tried to do the same thing with my previous backup (from which I had recovered most of my files) and it no longer worked either. I don't get an error message it just acts as if it ignored the double-click. I can access the backups using the restore dialog in TI2020, but I miss the ability to simply access the files directly (as if they had been mounted) - I've read a lot of posts concerning this method of opening a backup and am left confused - some say it works, some say it doesn't. The fact is, it worked a couple of days ago and now it doesn't  I haven't allowed any Windows updates and haven't updated Acronis. Does anyone have any idea why it would just quit working?